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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

15247 results found.

  1. GRB040825B: Correction to GCN 2657
  2. GRB 040812: Second epoch CXO Observations
  3. GRB040823,optical observation
  4. XRF040812: GMRT observations
  5. CXO observation of GRB 040812
  6. GRB 040810: Optical observations of a limited region
  7. GRB040624: optical monitoring at TNG
  8. XRF040701: First-Epoch Chandra Observations
  9. GRB040706:observation at University of Miyazaki
  10. XRF040701 (=U11548): a bright XRF detected by HETE
  11. GRB 040624: optical observations at TNG and VLT
  12. MASTER: GRB 040624 optical observation after 0,48d
  13. GRB 040624, optical observations
  14. GRB 030329: Rebrightening of hyperluminal ejecta.
  15. SGR 1806-20: no IR variability of the proposed counterparts
  16. MASTER:HETE Alert 3259 (SRG1806-20) optical observation
  17. SGR 1806-20, potential NIR counterpart
  18. GRB 040606: Optical observations
  19. GRB 040511: NIR observations with REM
  20. GRB040511: Optical Observations
  21. GRB040511 (=H3218): A Long GRB Localized by HETE WXM and SXC
  22. GRB 040423 (=H3175): A Long GRB Localized by HETE
  23. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  24. GRB 040422,optical observation
  25. GRB 040403: Optical observations
  26. GRB 040319 (=H3128): An X-Ray-Rich GRB Localized by the HETE-2 WXM and SXC
  27. GRB 031203: spectoscopic evidence for a 1998bw-like SN
  28. IBAS results on a burst from SGR1806-20
  29. IPN triangulation of GRB040228 (H3066, H3067)
  30. GRB 040228 (=H3066?,=H3067?): A Long GRB Localized by the HETE-2 WXM
  31. XMM-Newton Images of GRB 040223
  32. GRB 040223: REM IJK Observations
  33. GRB031220: 2nd Chandra observation and X-ray afterglow candidate
  34. GRB040106: refined X-ray transient position
  35. GRB040106, Radio Observations
  36. GRB 040106 : a long GRB detected with INTEGRAL
  37. GRB031220(=H2976): TNG R-band Observation of the Chandra X-ray Sources
  38. GRB031220(=H2976): Observation with the Chandra X-ray Observatory
  39. GRB 031203 I-band monitoring
  40. IPN triangulation of GRB031214 (short/hard; very intense; small error box)
  41. GRB 2974 follow-up observations
  42. GRB031203, improved XMM position
  43. GRB 021203: A Normal GRB viewed far off axis?
  44. GRB 031203: Variable Radio Source
  45. GRB 031203: Optical/IR Astrometry
  46. XMM-Newton Observation of GRB031203
  47. XMM-Newton Observation of GRB031203
  48. GRB 031203: Further reports on December 4 observations
  49. GRB 031203: IR NTTobservations do not confirm REM detection
  50. GRB 031203: Apparent Spectral Break
  51. GRB031203: Planned XMM-Newton observation II
  52. GRB 031203: A long GRB detected with INTEGRAL
  53. IPN triangulation of GRB031107 (two large error boxes)
  54. IPN triangulation of GRB031111 (=H2924): small error box
  55. XRF031109 (=H2919): A very long XRF localized by HETE
  56. SN 2003jd (SN/GRB?), Radio Observations
  57. SN 2003jd (SN/GRB?) - possible association with GRB 030929
  58. GRB 031026 (=H2882): Evidence for High Redshift from Prompt
  59. Peculiar Type Ic SN 2003jd (SN/GRB?), optical spectrum
  60. GRB031026 (=H2882): A Long, Hard Spectrum Burst Localized by HETE
  61. IPN triangulation of GRB031024 (annulus)
  62. IBAS alert 1180 refers to a burst from SGR 1806-20
  63. Ongoing Bursting Activity from SGR 1806-20 detected with IBAS
  64. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  65. A burst from SGR 1806-20 detected with IBAS
  66. XRF 030824: Early follow-up observation at Kiso observatory
  67. XRF030824 (=H2821): An X-Ray Flash Localized by the HETE WXM
  68. XRF030823 (=H2818): An X-Ray Flash Localized by the HETE WXM and SXC
  69. GRB030913: Subaru Optical Observations
  70. GRB 030913: ROTSE-3c Optical Observations
  71. GRB030913: OT's limit by MASTER
  72. GRB030913, candidate afterglow observations
  73. GRB030913: AAVSO optical observations
  74. GRB030913 (=H2849): Confirmation of the Flight Localization
  75. Magellan Observations of GRB030725 (=H2779)
  76. GRB030913 (=H2849): A GRB Possibly Localized by HETE
  77. XRF030824: Optical observations
  78. GRB 030824: Candidate Follow-Up
  79. XRF030824: Second-epoch Palomar observations
  80. XRF030824: optical observations
  81. GRB030823: optical observations
  82. GRB 030821(=H2814): A Faint, Long GRB Localized by the HETE WXM and the IPN
  83. 030813 SGR event (Konus-Wind observation)
  84. SGR 1808-20 (=H2802): A Possible new SGR
  85. XRF030723(=H2777): Chandra Fading X-ray Afterglow Confirmed
  86. XRF 030723: Detection of a rebrightening in the optical afterglow
  87. IPN triangulation of GRB030725 (=H2779; small error box)
  88. XRF030723 (=H2777): Second Epoch Magellan Observations
  89. GRB030725, optical transient observations
  90. XRF030723 Radio Observations
  91. XRF 030723: confirmation of fading optical counterpart
  92. XRF030723(=H2777): Chandra Observations
  93. XRF 030723: VLT spectra
  94. Magellan Observations of XRF030723 (=H2777)
  95. GRB030725, possible optical transient
  96. GRB030725 (=H2779): A Bright GRB Localized by HETE
  97. XRF030723: optical observations
  98. XRF030723, BVRcIc field photometry
  99. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  100. GRB030723, optical observations

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